not able to connect by bluetooth my macbook air and i phone 6

An iPhone will not pair via Bluetooth to a computer (Mac or Windows) except for personal hotspot and then only if your cellular plan supports it. See the following for more information. https://discussions.apple.com/docs/DOC-7722

If you are attempting to use Handoff/Continuity or AirDrop, that does involve Bluetooth but the devices are NOT paired; Bluetooth just needs to be on and the devices in range of each other. The following may help with Handoff/Continuity issues: https://support.apple.com/en-us/HT204678

Apple doesn't allow Iphones to connect via bluetooth to Macs.

You'll need to either connect via a cable or using wifi.